1. Field of the Invention
The present invention relates to the field of portable devices, and more particularly, to a method and apparatus for detecting insertion of a Subscriber Identity Module (SIM) card in a portable device.
2. Description of the Related Art
At present, Global System for Mobile communications (GSM) and Code Division Multiple Access (CDMA) are major wireless technologies for portable terminals. Most of Europe uses GSM, whereas CDMA is the most dominant standard in the U.S. Modifications of GSM and CDMA are also used. In some areas, multiple communication technologies are used jointly or in combination, for portable terminals.
Accordingly, recent portable terminals support dual modes or dual-standby functions so that a plurality of communication networks can be used with a single portable terminal.
A dual-mode portable terminal is booted selectively to one of a plurality of communication modes to thereby selectively use communication networks conforming to different communication standards, such as CDMA and GSM communication networks.
Unlike a dual-mode portable terminal, a dual-standby terminal can simultaneously use a plurality of communication networks (e.g. CDMA and GSM communication networks) without being booted selectively to one of the communication networks.
Each of the dual-mode portable terminal and the dual-standby portable terminal has one or more SIM cards inserted. For using a SIM card, the portable terminal needs to detect its insertion.
Conventionally, a separately configured sensor senses insertion of a SIM card. The use of the additional sensor requires additional hardware and increases fabrication cost.
Therefore, if insertion of a SIM card can be detected without using such an additional sensor(s), a portable terminal in which at least one SIM card is inserted, (i.e., a conventional, single mode portable terminal, a dual-mode portable terminal and/or a dual-standby portable terminal) can be fabricated smaller with lighter weight and for less cost.